Material feeding apparatus



Dec. 28, 1943'.

w. c:. STRIPE MATERIAL FEEDING APPARATUS Filed June 27, 1940 2 Sheets-Sheet 1 INVENT OR. 5 TR/PE MLL MM C/IRL Dec. 28, 1943. w. c. STRIPE MATERIAL FEEDING APPARATUS 2 Sheets-Sheet 2 INVENIOR. /4/ C ML STR/PE.

Filed June 27, 1940 Patented Dec. 28, 1943 MATERIAL FEEDING APPARATUS William Carl Stripe, Scarsdale, N. Y., assignor to Combustion Engineering Company,

York, N. Y.

Inc., New

Application June 27, 1940, Serial No. 342,659

4 Claims.

This invention relates to improvements in feeders for granular materials and particularly to flgeders for use with materials which tend to pao Although capable of other applications, the invention will be described as embodied in a fuel feeder forming part of a furnace Stoker. Some particles of coal are so small in size and sufficiently moist that they tend to pack on or adhere to surfaces of a feeding mechanism and thereby impair the continuity or predetermined rate of fuel feeding to the stoker. The type of feeder to which my invention is directed employs a rotating element for controlling the advance of I material through a throat or passage. It is an object of the invention to provide a rotating feeder element which is so constructed and arranged as to dislodge any material that adheres to surfaces with which it comes into contact while advancing.

How the foregoing, together with other objects and advantages as may hereinafter appear or are incident to my invention are realized, is illustrated in preferred form in the accompanying drawings, wherein:

Figure 1 is a sectional elevation through part of a fuel stoker embodying the invention.

Figure 2 is an enlarged end view of the rotary feeder shown in Figure 1; and

Figure 3 is a sectional view through the rotating feeder element taken on line 3-3 of Fig. 2.

Fuel flows through a conduit or hopper Ill to a throat or passage I l between a revolving feeder element designated as a whole by l2 and a coal plate l3 forming part of the feeder housing. The rotating element l2 comprises a shaft l4 having a plurality of independent members l5 placed side by side on the shaft and rotating therewith. The members I5 may have irregular peripheral surfaces for gripping the fuel such as teeth [6.

The feeder l2 in this instance is a part of a spreader stoker 2B and delivers the fuel to the distributer blades 2| which are revolved by any suitable means so that fuel dropping between the distributer blades, is propelled along the tray 22 and discharged through the opening 23 into the furnace. It will be seen that the rate at which the fuel is introduced into the furnace is dependent upon the rate at which the fuel is delivered to the revolving distributer blades 2| by the feeder I2. The rate of fuel flow past the feeder element to the stoker may be controlled by the speed with which the element is rotated or by the dimensions of the throat opposite the feeder where the latter revolves at a constant speed, or by a combination of the two.

Shaft [4 preferably is made square in cross section and each member It: has a central rectangular hole in its hub l l which fits loosely over the shaft, at least one dimension A of the hole being substantially greater than the dimension B of the square shaft l4. Thus, due to the pull of gravity and the pressure of the passing fuel member l2 will move transversely of the shaft by the amount of the clearance C between the hub and shaft at each half revolution of the shaft. Adjacent members I5 on shaft [4 are so mounted that the clearance C between shaft M and hub ll of one of them is at right angles to the clearance of the adjacent members. As shaft l4 rotates the adjacent members will then move radially in alternation at each quarter turn of the shaft by the amount of the clearancebetween hub and shaft. Consequently, the peripheral surfaces of the members simultaneously move out of alignment with respect to one another and this relative movement of the adjacent members dislodges any coal tending to adhere to the surfaces of the rotating feeder element.

Preferably I reduce the thickness of the hub of a member l5 at the sides where the opening in member 15 is widest to narrow the bearing l8 on shaft i l at these locations. I thereby lessen the tendency of fuel siftings to lodge between the shaft and the hub which would occur if the bearing were of considerable width, which might decrease or prevent the relative movement between members. I have maintained a full width of hub ll along the other sides of the shaft openings in members l5 as in this instance it is immaterial whether movement with respect to shaft It occurs in that direction. These longer hub widths maintain all the wheels at right angles to the shaft since each alternate wheel has a long hub at right angles to adjacent wheels.

Inasmuch as the fuel does not remain adhered to my improved rotating feeder element, the flow of fuel is at a rate substantially proportional to the speed at which the feeder element rotates.

What I claim is:

1. In a material feeder of the type described; a feeding member comprising a horizontally disposed rotary shaft; a plurality of feeding wheels each formed with a slot for mounting it on said shaft that has a length substantially greater than the thickness of said shaft; means operatively connecting said wheels to said shaft for rotation therewith, the width of the slot in the wheel being such as to provide a loose connection between the shaft and each wheel for permitting gravitational movement of the wheel along the length of the slot while at the same time securing each wheel against rotational movement on said shaft, adjacent wheels being so mounted on said shaft that the length of the slot in one wheel is at an angle to the length of slots in wheels at the sides thereoflsothat certain wheelsare displaced relatively to adjacent wheels at intervals during revolution of said shaft for repeatedly disrupting the peripheral alinement of said wheels.

2. Ina material feeder of the type described; a feeding member comprising a horizontally disposed rotary shaft; a plurality of feeding Wheelseach formed with a slot for loosely mounting-it on said shaft that has a length substantially greater than the thickness of said shaft and a width sufiiciently greater than the thickness of said shaft for fitting it on said shaft so as to be loosely mounted thereon and yet rotatable thereby, adjacent wheels being so mounted on said shaft that thellonger dimension of'ithe slot in one wheelisatian angle to: the longerdimension in th slots in wheels at the sides thereof, whereby all wheelsr move with respect to said shaft under the influence of gravity during rotation and certain wheels are displaced with) respect.

to adjacent Wheels on'said shaft at intervals duringrotation of the latter for repeatedly disrup ing the peripheral alinement of said Wheels.

3. Ina feeder'for delivering material through a passage, a rotating element, for controlling the advance of said material, comprising a square shaft, members mounted sidevby'sidexon' for the material in advance of said rotating element; means forming a passage for the materialvfrom the conduit adjacent said element and means for rotating said element.

4. In a feeder for delivering material through a passage, a rotating element for controlling the advance of said material comprising a square shaft, members mounted side by side on said shaft for rotation therewith having central hubs with rectangular holes tl'ierethrough which loosely fit over said shaft, one dimension of said holes being greater than the other dimension'and such other dimension being at right angles to the greater dimension of thehole of the next adjacent member thereby causing transverse movement with respect to said shaft and the adjacent member, the hub of each member adjacent the reater dimension of said hole being of relatively narrower widthialong the shaft than the hub J adjacent the smaller dimension.

WILLIAM CARL STRIPE. 

